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    <meta charset="UTF-8">
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    <title>Document</title>
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        .img {
            width: 300;
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            border-radius: 50%;
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    <img src="" alt="这是一只狗" class="img" >
    <img src="https://img0.baidu.com/it/u=1927296016,361273946&fm=253&fmt=auto&app=120&f=JPEG?w=889&h=500" alt="一个白色的狗" class="img">
</body>
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